This invention relates to a jack, and in particular to a jack for a vehicle or another heavy load.
In general, jacks are mechanical structures including some form of rack and a pawl engaging the rack for movement therealong. Because all of the elements of existing jacks including the drive thereof are usually manufactured from scratch and are often somewhat complicated, the device may be expensive.
The present inventor is aware of patented jacks having features in common with the invention proposed herein. The jacks in question are described in U.S. Pat. Nos. 169,139, which issued to M. J. Walsh on Oct. 26, 1875; 1,610,850, which issued to F. A. Davidson on Dec. 14, 1926; 2,189,665, which issued to I. Kirby on Feb. 6, 1940 and 2,222,243, which issued to O. E. Sandstrom on Nov. 19, 1940. The patented devices are of interest, because they include mechanisms bearing some, albeit remote, similarity to the device proposed by applicant.
The object of the present invention is to solve the above-identified problem while improving on existing jack structures by providing a relatively simple jack which is produced from readily available, off-the-shelf hardware, and which can be operated manually or by means of a pneumatically, hydraulically or electrically operated socket wrench.